Electrical connector



N. R. SMITH ELECTRICAL CONNECTOR Sept. 21, 1943.

Filed Dec. 31, 1941 INV ENTOR JVmazZlZ.

Patented Sept. 21, 1943 ELECTRICAL CONNECTOR neweu R. Smith, Bloomfield,N. J., assignor to Radio Corporation of America, a corporation ofDelaware Application December 31, 1941, Serial N p 425,029

2 Claims. (cl. 173-323 tween closely spaced conductors is limited by thedielectric medium between the conductors. The dielectric constant of airis lower than the dielectric constant of many of the common insulatingmaterials, such as rubber and plastics of the Bakelite type, and it isfound that the rarefied atmosphere, encountered in .high altitudeoperation of aircraft, exhibits the peculiar property of ionizing andcausing arc-over between exposed conductors at comparatively low'voltages. Arc-over failures of sockets are usual- 1y caused by arcsalong air paths between the conductors, and not through the solidinsulation.

An object of my invention is connectors with male and female connectorelements which effectively close all air paths between adjacent wiresand contacts.

In accordance with my invention the socket body of the female connectorelement is provided with a plurality of female contactors set into thebody with openings in the surface of the body communicating with eachfemale contactor, the openings each being flared at its outer end toform a conical recess in said surface. The plug, base or male element ofthe combination comprises an insulating plate with a plurality of cntactpins arranged to register with the female contactors of the socket. Eachpin of the base is attached to the apex of a frustum, or conical filletor knob, the taper and size of the frustum being the same as that of therecess in the socket. When the pins of the base are pushed home in thefemale socket contactors, the conical fillet of the base is seated inthe conical recess of the socket. By providing for slight side-waysmovement of the female contactors, the cones of the base may be made toaccurately seat in the recess and completely close all air paths betweenany two pins.

The characteristic features of my invention are defined in the appendedclaims and on embodiment thereof is described in the followingspecification and shown in the accompanying drawing in which Figure 1shows'in section my novel combination of male and female connectorelements and Figure 2 shows, in perspective, the combination of Figure1.

By way of illustration, my novel combination of male and femaleconnector elements is shown as a base and socket for a conventionalradio tube. 'The socket body 1 i preferably of molded insulatingmaterial, such as a plastic of the type commercially known as "Bakeliteand is provided with a series of openings 2 arranged in a circleconcentric with the body. In each opening is placed a tubular femalecontactor 3 connected at its lower end, preferably by welding orsoldering, to a conductor 6. The upper end of the opening is flared toform a conical recess 5 in the top surface of the socket body. It hasbeen found convenient to pre-form or cast the socket body in two membersla and lb, as shown in Figure 1, and to assemble the two pieces with Ythe several metal iemale contactors locked into their respectiveopenings by ledges or shoulders 'B on the inner member.

The base or male element 7 may likewise comprise a body of moldedinsulating material with the pins 8 arranged on the base to registerwith the female contactors. Each pin is supported at the apex of acone-shaped fillet or right conical frustum 9, the sides of which aretapered with the same slope as the recess so that when the pins arepressed home in the socket each fillet seats snugly in the recess. Onlyslight pressure is necessary to insure good seating and effectiveclosure of the air paths between the pins. A- thin coating of wax,grease or similar viscous insulating ointment applied to the surface ofeither the conical recess or fillet will insure an airtight closure ofthe air paths and permit slight variations in both the taper of thecones and in spacings between the cone centers and still maintain ahermetic seal.

The insulating covering M on each wire conductor is preferably carriedto the point where th conductor is joined to the lower end of the femalecontactor. In assembly, the contactors,

with wires attached, are laid in longitudinal rooves on the ,side ofinner socket member lb, with the notch of th contactor astraddle theshoulder 6. The outer socket member is then slipped over the assembledcontactors and inner member. The edge of the skirt of the outer memberis preferably rounded so that it will ride onto and squeeze the wireinsulation and hence effectively seal the bottom end of the socketopenmg.

Tests at high voltages in rarefied atmospheres show that bases andsockets made according to my invention will not fail due to arcing orflashover at voltages which would destroy bases and sockets of ordinaryconstruction. Fins ill within the base insulatingly partition theconductors to prevent arc-over there.

My novel base and socket may be made by the standard base making methodsand the air seals between pins are insured merely by pressing home thebase in its socket.

I claim:

1. A socket body comprising an inner cylindrical member of insulatingmaterial, said inner member having a plurality of grooves longitudinallyalong the outer surface of said inner member, a tubular female contactorlaid in each groove, and a tubular outer insulating member telescopedover said inner member and over the contactors in their" grooves, andmeans to hold the contactors in place, a conical recess in the socketbody in coaxial alignment with one end of each of said grooves, a wireinserted in the opposite end of each oi'said grooves and consealedair-tight with the walls or the grooves at said opposite ends.

2. An electrical socket comprising an inner cylindrical member orDre-formed molded insulating material, said inner member having aplurality of longitudinally extending grooves along the outer surface orsaid inner member, a tubular female contactor in each groove, means tohold the contactors against longitudinal movement in said grooves,.and atubular outer member oi. pre-iormed molded insulating materialtelescoped over said inner member and over the contactors in theirgrooves, a recess in the socket members in coaxial alignment with oneend of each of said grooves, a wire extending into the opposite end ofeach of said grooves and connected to a contactor, an insulatingcovering on each wire each covering being wedged between the walls ofsaid grooves and the inner surface nected to a contactor. an in at ncovering 0 20 of said outer member.

each wire, each covering being wedged in and NEWELL R. sm'rn.

